Winding for dynamo-electric machines



H. MATTHEWS.

WINDING FOB DYNAMO ELECTRIC MACHINES.

APPLICATION FILED SEPT-7,1917.

Patented Apr. 12, 1921.

INVENTOR fia/ry ll/a ffkews above-described character.

UNITED STATES PATENT OFFICE.

H ARRY MATTHEWS, OF EDGEWOOD PARK, PENNSYLVANIA, AS SIGNOR TO WESTIN G- HOUSE ELECTRIC & MANUFACTURING COMPANY, A CORPORATION OF PENNSYL- VAN IA.

WINDING FOR DYNAMO-ELECTRIC MACHINES.

Specification of Letters Patent. Patented Apr. 12, 1921.

Application filed September 7, 1917. Serial No. 190,099.

To all whom it may concern Be it known that I, HARRY MA'rTHnws, a citizen of the United States, and resident of Edgewood Park, in the countyof Allegheny and State of Pennsylvania, have invented a new and useful Improvement in VVindings for Dynamo-Electric Machines, of which the following is a specificat on.

My invention relates to windings for dynamo-electric machines and it has particular relation to the so-called squirrel-cage windings with which the secondary members of induction motors and similar apparatus are provided The object of my invention is to provide means for preventing displacement of the conducting bars comprising windings of the In the accompanying drawings, Figure l is a view, partially in section and partially in end elevation, of a portion of the second ary member of an induction motor embodying my invention; Fig. 2 is a deve loped plan view of the parts shown in Fig. 1; parts being broken away and removed from their normal positions to show my invention more clearly and Fig. 3 is a vlew, s1m1lar to Fig. 1, showing a modification of my 1I1- vention. v

A laminated magnetizable core member 1 is provided with a plurality of partiallyclosed peripheral slots 2 within which are located conducting bars 3. The total crosssectional area of each bar 3 is slightly less than thatof a slot 2 and, as best shown in Fig. 2, each bar is provided with offset portions 4. The off-set portions 4 are shown in exaggerated form and are, in practice, made to project from the surface of the bar for a distance that is slightly greater than the distance A which represents the difference between the normal thickness of a bar and the width of a slot. In Fig. 3, the offset portions 4 of thebars 3 are arranged to compensate for the difference between the radial depth of a bar and that of a slot which is represented by the distance B.

From the foregoing, it is apparent that the bars 3 may be partially inserted within the slots 2 without the application of force. However, when the off-set portion 4 of a bar engages the bottom or a side wall of a slot 2, the plane surface of the bar engages the opposite wall of the slot and it is then necessary to apply considerable force to drive the bar farther into theslot. When a bar is finally driven into position, it is very diflicult to displace it because the off-set portions at slightly bend over the edges of the laminations comprising the core member and thus tend to lock the bar in position. When all of the conducting bars have been applied to the core member, it is possible to true up the ends of the bars without danger of the bars beingdisplaced when subsequent operations are performed upon them, as, for

example, in attaching end rin s thereto.

I I o y 1 Wh1le I have shown my invention in its simplest and preierred forms, itis not so limited but is susceptible of other changes.

and modifications within the scope of the appended claims. I claim as my invention:

1. In a dynamo-electric machine, the combination with a core member provided with a plurality of longitudinally extending slots, of conducting bars located in the slots and having offset portions thereof in positive engagement with the bounding surfaces of the slots.

2. In a dynamo-electric machine, the combination with a core memberprovided with a plurality of longitudinally extending slots, of conducting bars located in the slots, and respectively provided with offset portions in the central portion thereof to prevlent displacement of the bars within the s ots.

3. In a dynamo-electric machine, the com- 1 bination with a core member provided with a plurality of longitudinally extending slots, of conducting bars located in the slots, and provided with ofi'set portions within said slots that are unsymmetrical with respect to the longitudinal axes of said bars.

4. In a dynamo-electric machine, the combination with a core member provided with a plurality of longitudinally extending slots, of conducting bars located in the slots, the said bars and the slots having different cross sectional areas and each bar having an offset portion within the slots portion in engagement with the core member.

5. In a dynamo-electric machine, the combination with a core member provided with a plurality of longitudinally extending slots, of conducting bars located in the slots, the said bars and the slots having different cross sectional areas and each bar having sideportions thereof a ternately in engagement with the core member.

6. In a dynamo-electric machine, the combination with a core member provided with a plurality of longitudinally extending slots, of conducting bars located in the slots, discontinuous side portions of each bar be ing in engagement with the core-member.

7 In a dynamoelectric machine the combination with a core member provided with a plurality of longitudinally extending slots, of conductor bars of smaller crosssection adapted to be inserted within said slots those portions of the bars normally within said slots being so formed as to re- .bination with a core member provided with a plurality of longitudinally extending slots, of conducting bars of sinuous contour and of constant cross-section disposed within said slots. 7

10. In a dynamo-electric machine, the combination with a core member provided with a plurality of longitudinally extending slots, oi conducting. bars disposed within said slots each provided with an indentation on one side thereof and with oflset portions on the other side thereof. said off et portions only engaging the walls of said slot.

11. In a dynamo-electric ins/chine the combination with a core'member provided with a plurality of longitulinally extending slots of conducting bars disposed within said slots each provided with spaced oflset portions alternately disposed on the two sides thereof, the width of said conductors at any point being less than that of the slots but the width over the ends of said offset portions being normally slightly greater than that of the slots.

in testimony whereof I have hereunto subscribed my name this 23d day of August, 1917.

. HARRY MATTHEXVS 

